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Ground-penetrating radar (GPR) is an effective geophysical electromagnetic method for underground target detection. However, the target response is usually overwhelmed by strong clutter, thus damaging the detection performance. To account for the nonparallel case of the antennas and the ground surface, a novel GPR clutter-removal method based on weighted nuclear norm minimization (WNNM) is proposed, which decomposes the B-scan image into a low-rank clutter matrix and a sparse target matrix by using a non-convex weighted nuclear norm and assigning different weights to different singular values. The WNNM method's performance is evaluated using both numerical simulations and experiments with real GPR systems. Comparative analysis with the commonly used state-of-the-art clutter removal methods is also conducted in terms of the peak signal-to-noise ratio (PSNR) and the improvement factor (IF). The visualization and quantitative results demonstrate that the proposed method outperforms the others in the nonparallel case. Moreover, it is about five times faster than the RPCA, which is beneficial for practical applications.
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The construction industry consumes substantial water resources. Thus, there is a necessity to adopt effective water-saving measures to reduce water consumption in construction projects. The aim of this paper is providing a strategic framework of water-saving measures for different phases of a construction project. To start with, the prevailing green building rating tools were investigated to explore the alternative water-saving measures. Then, a comparative analysis utilizing relative significance indexing was conducted to identify the foci of water-saving measures in various green building rating tools. Based on the derived results, ten water-saving measures, namely rainwater harvesting, usage of recycled water, NEWater, water-saving technologies, water-saving devices, water-saving efficiency, water monitoring system, monitoring of major water uses, leak detection, and continuous water monitoring, were identified. These measures were further categorized into three strategic aspects, such as water sources substitution, water consumption reduction, and water use monitoring. Based on the results, a strategic framework was developed for reducing water consumption and improving water use efficiency. The developed framework can serve as a systematic guideline for formulating water-saving schemes in different stages of construction projects.
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Conservación de los Recursos Hídricos/métodos , Industria de la Construcción/métodos , Agua , ReciclajeRESUMEN
With the acceleration of urbanization in recent years, China has witnessed large-scale construction across its provinces, generating massive amounts of construction waste that pose challenges to environmental protection and sustainable development. This study evaluated the impact of construction waste policy intensity on its environmental efficiency. Firstly, the content analysis method was used to analyze the construction waste policy text quantitatively. Second, this study constructed a slack-based measure (SBM) model based on data envelopment analysis (DEA), considering resource input and construction waste output to measure environmental efficiency. Finally, we built and tested an econometric model of how policies affect environmental efficiency using the system generalized method of moments (SYS-GMM). The findings indicate a non-linear U-shaped link between policy intensity and environmental efficiency. Among all five control variables, population density, urbanization level, and technological innovation enhance environmental efficiency, while economic development and highway density will lower it. This study advances the research on construction waste policies and offers some insights for the construction industry to pursue sustainable development.
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Conservación de los Recursos Naturales , Desarrollo Sostenible , Urbanización , China , Invenciones , Eficiencia , Desarrollo Económico , Política AmbientalRESUMEN
The rapid urban renewal progress has generated a large amount of construction and demolition (C&D) waste in China. According to the concept of circular economy (CE), producing products with recycled content (PwRC) is an effective solution to achieve sustainable C&D waste management. However, the low market acceptance of PwRC affects stakeholders' purchase intention, which hinders the development of the PwRC industry. In order to clarify the stakeholders' purchase intention and investigate the influencing mechanism of stakeholders' purchase intention, a novel method which combines structural equation modeling (SEM) with a back-propagation neural network (BPNN) is proposed. The method makes full use of the causal analysis ability of SEM and the nonlinear characteristics of BPNN to simulate and to verify the path of product cues, perceived value, and behavioral intention of stakeholders. The results reveal that the brand and materials of PwRC can affect stakeholders' perceived value, and in turn, affect their purchase intention. Focus on the brand and materials of PwRC will help recycled product manufacturers and governments to promote stakeholders' purchase intention and the development of the C&D waste recycled products market.
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Industria de la Construcción , Intención , Análisis de Clases Latentes , Comportamiento del Consumidor , ReciclajeRESUMEN
INTRODUCTION: We investigated the role of macrophage migration inhibitory factor (MIF) on dendritic cells (DC) during acetaminophen (APAP)-induced acute liver injury (ALI) in mice. METHODS: First, we randomly divided the mice into experimental (ALI model) and control groups, then intraperitoneally injected 600 mg/kg of APAP or phosphate-buffered saline, respectively. Then, we collected liver tissue and serum samples to evaluate liver inflammation using serum alanine aminotransferase level and hematoxylin and eosin (H&E) staining of liver tissues. Flow cytometry was used to identify changes in the quantity and percentage of DCs, as well as the expression of cluster of differentiation (CD) 74 and other apoptosis-related markers in the liver. Next, we randomly divided the mice into APAP-vehicles, APAP-bone marrow-derived dendritic cells (BMDCs), APAP-MIF, APAP-IgG (isotype immunoglobin G antibody) groups (four mice per group), after APAP injection, we injected control extracts, BMDCs, mouse recombinant MIF antibodies, or IgG antibodies into the tail vein. Lastly, the severity of the liver injury and the number of DCs were assessed. RESULTS: The APAP-induced ALI mice had increased hepatic MIF expression but significantly lower amounts of hepatic DCs and apoptotic DCs than healthy mice; CD74 expression on the HDCs also increased markedly. Supplementing APAP-induced ALI mice with BMDCs or MIF antibodies significantly increased the number of hepatic DCs compared with the control mice, alleviating liver damage. CONCLUSION: The MIF/CD74 signaling pathway may mediate hepatic DC apoptosis and promote liver damage.
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Enfermedad Hepática Crónica Inducida por Sustancias y Drogas , Factores Inhibidores de la Migración de Macrófagos , Animales , Ratones , Acetaminofén/toxicidad , Apoptosis , Células DendríticasRESUMEN
INTRODUCTION: Work-related musculoskeletal disorders (WMSDs) are recognized as a leading cause of nonfatal injuries in construction, but no review of existing studies has systematically analyzed and visualized the trends of WMSDs among construction workers. The current science mapping-based review summarized research published between 2000 and 2021 related to WMSDs among construction workers through co-word, co-author, and citation analysis. METHOD: A total of 63 bibliographic records retrieved from the Scopus database were analyzed. RESULTS: The results identified influential authors with high impacts in this research domain. Moreover, the results indicated that MSDs, ergonomics, and construction not only had the highest occurrence of been studied, but also the highest impact in terms of total link strength. In addition, the most significant contributions to research relating to WMSDs among construction workers have originated primarily from the United States, Hong Kong, and Canada. Furthermore, a follow-up in-depth qualitative discussion was conducted to focus on summarizing mainstream research topics, identifying existing research gaps, and proposing directions for future studies. CONCLUSIONS: This review provides an in-depth understanding of related research on WMSDs among construction workers and proposes the emerging trends in this research field.
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Industria de la Construcción , Enfermedades Musculoesqueléticas , Enfermedades Profesionales , Humanos , Estados Unidos , Factores de Riesgo , Enfermedades Musculoesqueléticas/epidemiología , Enfermedades Musculoesqueléticas/etiología , Ergonomía , Hong Kong , Enfermedades Profesionales/epidemiología , Enfermedades Profesionales/etiología , PrevalenciaRESUMEN
Titanium selenide (TiSe2 ), a model transition metal chalcogenide material, typically relies on topotactic ion intercalation/deintercalation to achieve stable ion storage with minimal disruption of the transport pathways but has restricted capacity (<130 mAh g-1 ). Developing novel energy storage mechanisms beyond conventional intercalation to break capacity limits in TiSe2 cathodes is essential yet challenging. Herein, the ion storage properties of TiSe2 are revisited and an unusual thermodynamically stable twin topotactic/nontopotactic Cu2+ accommodation mechanism for aqueous batteries is unraveled. In situ synchrotron X-ray diffraction and ex situ microscopy jointly demonstrated that topotactic intercalation sustained the ion transport framework, nontopotactic conversion involved localized multielectron reactions, and these two parallel reactions are miraculously intertwined in nanoscale space. Comprehensive experimental and theoretical results suggested that the twin-reaction mechanism significantly improved the electron transfer ability, and the reserved intercalated TiSe2 structure anchored the reduced titanium monomers with high affinity and promoted efficient charge transfer to synergistically enhance the capacity and reversibility. Consequently, TiSe2 nanoflake cathodes delivered a never-before-achieved capacity of 275.9 mAh g-1 at 0.1 A g-1 , 93.5% capacity retention over 1000 cycles, and endow hybrid batteries (TiSe2 -Cu||Zn) with a stable energy supply of 181.34 Wh kg-1 at 2339.81 W kg-1 , offering a promising model for aqueous ion storage.
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Public participation is an important procedure of the environmental impact assessment. Effective public participation is essential to the Public-Private Partnership (PPP) projects as such projects usually exert tremendous impacts on the environment and society. However, in literature, there are few studies investigating the driving factors of public participation in PPP projects, especially in the context of China. To bridge this research gap, this study proposed a theoretical model, which incorporates contextual factors (i.e., perceived benefit and perceived risk) into the classical Theory of Planned Behavior model, to explore the determinants. The initial proposed model was tested using structural equation modeling. Analysis results indicated that attitude towards behavior, subjective norm, perceived risk and perceived behavioral control were the four significant driving factors of public participation in PPP projects, whereas perceived benefit had limited impact. Furthermore, this study evaluated eight public participation approaches in PPP projects. Results revealed that the public were more willing to participate in public decisions through the internet platform, followed by the information disclosure or consultation provided by the government. The research findings derived in this study can provide valuable reference for the government to promulgate proper policies to attract more public participation in PPP projects. Moreover, the research idea and methods used in this study can be popularized in other countries to enhance the public participation in PPP projects.
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Gobierno , Asociación entre el Sector Público-Privado , China , Participación de la Comunidad , Humanos , PolíticasRESUMEN
The study of construction and demolition waste (CDW) has attracted more and more attentions with the increasing CDW pollution caused by the large-scale infrastructure construction. This study used the Latent Dirichlet Allocation (LDA) combined with topic intensity to discover hot topics and development trends in the study area of CDW. First, the LDA was used for topic modeling to extract the existing topics from textual data. Second, the topic intensity was calculated for the extracted topics and the numerical values of the topic intensity represented the popularity of the topics. In this study, 4 topics were extracted from 1,849 relevant articles through the LDA modeling and topic intensity calculation. The results showed that the topic of "CDW management" had an upward trend. Topics such as "recycled aggregate," "environmental impact," and "study of CDW on soil" all showed a downward trend. The methods of this study can dig into the topics of CDW study and help scholars to engage in this field for better understanding the prevalence and evolution trends of these topics.
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Industria de la Construcción , Administración de Residuos , Materiales de Construcción , Ambiente , Reciclaje/métodos , Administración de Residuos/métodosRESUMEN
The world is undergoing an unprecedented trend of fast urbanization, which causes a range of socio-environmental consequences, one of which is shrinking cities and towns (SCT). SCT refer to the cities or towns that are experiencing population decline and economic downturn. In the existing literature, there have been numerous studies on SCT; however, there is a lack of study which investigates its knowledge domains. Therefore, this paper aims to conduct a scientometric analysis to achieve an outline of the SCT research status. Through the procedures of literature search and screening, a total of 716 SCT-related studies were extracted from the Scopus. The VOSviewer software system program was then utilized to visualize the present SCT-related studies. The visualization results revealed that the journal of Sustainability made significant contributions to the SCT research in terms of relevant publications. In addition, Haase, Annegret received the most co-citations, and was also the most productive author in this field. Furthermore, it was identified that current SCT research is mainly conducted in developed countries. Through the analysis of keywords, the emerging research topics were revealed. Discussions were further made from the perspectives of prevailing research methods, evaluation criteria, and solutions for SCT problems.
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Bibliometría , Urbanización , Animales , Ciudades , Recolección de Datos , Dinámica PoblacionalRESUMEN
Adoption of prefabrication is essential for improving the urban built environment. However, the existing prefabrication market in China is far from mature. As the stakeholder who conducts construction activities, the contractor is facing a dilemma of lacking steady prefabricated components supply. In this circumstance, a potential solution is that contractors open their own prefabrication factories to guarantee stable component supply. The aim of this research is exploring the key factors for contractors to open prefabrication factories. Firstly, a total of 28 influencing factors were identified from literature. Then, the identified factors were divided into four categories: policy environment, market environment, technological environment, and enterprise internal environment. Through interviews with experienced professionals, a total of 19 factors were selected for future analysis. Based on the 19 factors, a questionnaire was designed and distributed to the experts to rate the degree of mutual influences. The collected data were analyzed using Ucinet6.0 software, and the adjacency matrix and the visual models were established. Finally, through the analysis of node centrality, betweenness centrality, and closeness centrality, the four key influencing factors were determined including mandatory implementation policy, precast concrete component's price, market demand, and contractor's strategic objectives. The results of this study could assist contractors in making decisions of opening their own prefabrication factories toward more sustainable environment.
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Industria de la Construcción , China , Toma de Decisiones , Políticas , Encuestas y CuestionariosRESUMEN
With the acceleration of urban development, the amount of municipal solid waste (MSW) has increased dramatically. In order to recycle MSW more efficiently, a compulsory policy of sorting MSW has been enacted in China. According to the existing literature, attitude is an important factor affecting public's MSW sorting behavior. To explore the Chinese residents' emotional tendency towards the MSW sorting policy, this study analyzed the data of Sina Weibo users and their comments on related popular posts. Meanwhile, text mining technology was employed to analyze the collected data. Results showed that although a large proportion of the Chinese public has a positive attitude towards the MSW sorting policy, the proportion of people with negative emotions reached nearly half. In addition, it was found that the Chinese people in different regions pay different attentions to the MSW sorting policy. Results further revealed that the main reasons for the public's negative emotions were fines, MSW sorting rules, fees, timing of throwing waste, and irregular recycling procedures. By providing the public sentiment analysis of MSW sorting, this study can serve as a policy guide for practitioners and policy-makers to link current research areas into social development.
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In recent years, building information modeling (BIM) has been receiving growing interest from the construction industry of China. Nevertheless, although BIM has many foreseeable advantages, many studies claimed that these advantages have not been sufficiently achieved in practice at the current stage. In this circumstance, it is interesting to investigate what really drives the adoption of BIM. Based on Ajzen's theory of planned behavior (TPB), a hypothetical model which involves nine latent variables is initially established. Then, a questionnaire is designed and distributed to the construction professionals in the Chinese context. After reliability and validity analysis, the goodness-of-fit of the initial model and the related theoretical assumptions are tested through structural equation modeling (SEM). Based on the modification indicators, a modified model is finally derived. Results show that economic viability and governmental supervision are the most critical factors that influence construction professionals' BIM adoption behavior in China, sharing weights of 0.37 and 0.34, respectively, whereas other factors play limited roles in this regard. The research findings revealed from this study can provide insightful references for countries that intend to promote BIM adoption in a similar circumstance.
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Industria de la Construcción , China , Humanos , Teoría Psicológica , Reproducibilidad de los Resultados , Encuestas y CuestionariosRESUMEN
Gated communities are the most popular residential pattern in the urban areas of China. However, along with the increasing population density in urban areas, this pattern may have negative influences on people's daily lives, such as traffic jams. To avoid the negative influences, the government has encouraged residents to open their gated communities; however, few positive actions have been taken. With this background, this study aims to explore the key factors in residents' willingness to open their gated communities. To start with, a total of 26 potential factors were identified based on a comprehensive literature review. Then, a questionnaire was designed and distributed to collect empirical data. Furthermore, logistic regression was employed to analyze the collected data. Based on the derived results, it was revealed that concerns are different between male and female residents. Male residents regarded "community safety" and "property management" as having a significant impact on their decision to open a gated community, while female residents paid more attention to the factor of "proprietary equity". The results of this study could provide valuable references that enable the government to better understand residents' underlying concerns and to make relevant policy decisions.
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Políticas , China , Femenino , Humanos , Masculino , Encuestas y Cuestionarios , Población UrbanaRESUMEN
As a game-changing technology with significant environmental, economic, and social benefits, prefabricated technology has attracted attention and has been increasingly adopted in the construction industry. Although multitudinous studies have investigated various aspects of prefabrication in construction, a thorough review of its current development state that synthesized environmental, economic, and social sustainability dimensions remains overdue. Therefore, this study aims to fill this research gap by constructing a systematic framework, analyzing the research status quos, and providing recommendations for future research. This study first conducted a holistic review of 768 references with NVivo. A research foci framework that represented the body of knowledge in prefabrication in construction was developed with five levels, which were advantages, hindrances, stakeholders, promotion policies, and strategy spectrum. Following the framework, the in-depth analyses from the perspectives of environmental, economic, social sustainability, technologies development, and promotion strategies were performed. The current research domains were further linked with potential research directions for promoting prefabricated construction towards sustainability. The study is of value in both offering references for policy formulation and stakeholder practice and providing recommendations for future research.
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Industria de la Construcción , PolíticasRESUMEN
In recent years, with the development of green building and the increase of health awareness, the concept of healthy building has been proposed. Recently, studies have been made on developing healthy residential buildings; however, few attentions have been paid to the development of healthy dormitories. To bridge this research gap, this paper aims to investigate the crucial aspects of developing a healthy dormitory. Based on the Maslow's hierarchy of needs, three influencing aspects which include 17 measurement indicators are identified. Questionnaire surveys are subsequently conducted to collect students' perceptions on the identified indicators. After a structural equation modeling (SEM) analysis, the relationships between the three influencing aspects are analyzed. The research findings show that building performance, bodily sensation, and humanistic environment must be taken into account in the development of a healthy dormitory. In addition, it is revealed that building performance has a significant impact on bodily sensation, while bodily sensation has a significant impact on humanistic environment. However, building performance is found having little impact on humanistic environment. The findings of this study could provide useful information for the construction of healthy dormitories.
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Vivienda/normas , Estudiantes , China , Humanos , Encuestas y CuestionariosRESUMEN
China has enacted numerous green building policies (GBPs) to promote green building (GB) development in the past decades. Investigating the evolution characteristics of China's GBPs is significant for the future optimization of the GBP system. However, few studies on this topic have been conducted. To bridge this research gap, this paper adopted the methods of bibliometric analysis and text mining to probe the dynamic evolution of the GBPs in China. Firstly, a total 199 collected policies from 1986 to 2019 were grouped into five stages according to the Five-Year Plan. Then, the topics emphasized in different stages and the cooperative relationships among policymaking agencies were discovered by mapping and visualizing the co-word network and co-author network. Based on the derived results, an in-depth discussion was further conducted from five aspects: targets, objects, instruments, GB performance indicators, and the collaboration structure of policymaking agencies. It was revealed that the topics of GBPs evolved from macro to specific, and the types of policy targets, objects, instruments, and GB performance indicators evolved from few to multiple. Additionally, the collaboration structure of policymaking agencies went from dispersive to centralized. This study sheds lights on the dynamic evolution of China's GBPs and provides valuable references for other countries in need.
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Formulación de Políticas , Desarrollo Sostenible , China , PredicciónRESUMEN
With the rapid development of the economy, people are paying more and more attention to the environmental problems. In this circumstance, the concept of a circular economy is proposed for making efficient use of resources and minimizing the production of waste and other emissions. Each year, the construction sector consumes a vast volume of resources and makes impacts on the environment. To align with the development of the circular economy, the concept of green building is proposed. In China, though the concept of green building has been promoted for decades, the development status is far from optimistic. Thus, this paper aims to investigate the barriers that hinder green building development (GBD) in China. Through a systematic review and semi-structured interviews with experienced industrial practitioners, 24 potential barriers of GBD in China were identified. A questionnaire survey was then conducted for data collection. After descriptive and inferential statistical analyses, a partial least squares structural equation model (PLS-SEM) was established to investigate the impacts of different barriers on GBD. Results showed that the lack of policy and industry guidance, the immature market environment, and the lack of environmental awareness are the most important GBD barriers in China. This research can assist stakeholders in better understanding the status of GBD in China and enable decision-makers to formulate appropriate strategies to promote green building.
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Conservación de los Recursos Naturales , Industria de la Construcción , China , HumanosRESUMEN
Visualization is one of the main features of Building Information Modeling (BIM). It has many advantages throughout the lifecycle of a construction project, and it has become a timely research topic in recent years. However, no attempt has been made to give a holistic understanding of the existing BIM-based visualization research status. Thus, this study aims to conduct a scientometric analysis of the existing BIM-based visualization literature and to gain a snapshot of the research status during the period 2010-2019. A total of 255 articles were abstracted from the Scopus database. Then, the VOSviewer program was employed to visualize the research status from the perspectives of scholars, countries/regions, journals, articles, and co-occurring keywords. Results revealed that Wang X. published the greatest number of articles, while Cheng J.C.P. received the greatest average normalized citations. Furthermore, Automation in Construction was identified as the most influential journal and the article "Building information modeling (BIM): trends, benefits, risks, and challenges for the AEC industry" was the most cited paper. Through the keywords co-occurrence analysis, "virtual reality" and "visual programming language" were identified as the emerging themes in this field. The research findings can provide both researchers and practitioners with a better understanding of the status quo and trends of the BIM-based visualization research.
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Industria de la Construcción/métodos , Realidad Virtual , Bibliometría , HumanosRESUMEN
With the recent fast economy development and rapid urbanization, the huge generation of construction waste has become a threat to sustainable development in China. Though efforts have been made to promote reuse and recycling of construction waste, landfilling of waste remains the most commonly adapted approach for construction waste disposal. As the space for landfills is limited and because of the negative issues in terms of environmental and social aspects that may be caused, the appropriate site selection of landfills is crucial. With this background, this paper aims to establish a framework for facilitating landfill selection for construction waste. To begin with, a total of sixteen factors that may influence landfill site selection were identified from a literature review. Then, based on the combined analytic hierarchy process (AHP) and entropy method, the weights and the final comprehensive scores of the identified factors were calculated. According to the derived results, potential sites for landfills were divided into three levels, namely the most appropriate (0.38%), appropriate (17.58%), and inappropriate (82.04%). The proposed decision-making methods in this paper can provide a valuable reference for the selection of construction waste landfill sites.